Four processes (T. C. Patton, Pigment Handbood, Volume 1, New York 1973, page 333) are generally employed for the preparation of red iron oxide pigments but no simple, economical and at the same time environmentally safe method has yet been found for the production of iron oxide red pigments which are pure in color and low in foreign metal content.
It is an object of the present invention to provide improved iron oxide red pigments which are economically obtainable by a technically simple process.